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1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Copyright (C) 2014 Linaro Ltd.
4 * Author: Rob Herring <robh@kernel.org>
5 *
6 * Based on 8250 earlycon:
7 * (c) Copyright 2004 Hewlett-Packard Development Company, L.P.
8 * Bjorn Helgaas <bjorn.helgaas@hp.com>
9 */
10
11#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
12
13#include <linux/console.h>
14#include <linux/kernel.h>
15#include <linux/init.h>
16#include <linux/io.h>
17#include <linux/serial_core.h>
18#include <linux/sizes.h>
19#include <linux/of.h>
20#include <linux/of_fdt.h>
21#include <linux/acpi.h>
22
23#ifdef CONFIG_FIX_EARLYCON_MEM
24#include <asm/fixmap.h>
25#endif
26
27#include <asm/serial.h>
28
29static struct console early_con = {
30 .name = "uart", /* fixed up at earlycon registration */
31 .flags = CON_PRINTBUFFER | CON_BOOT,
32 .index = 0,
33};
34
35static struct earlycon_device early_console_dev = {
36 .con = &early_con,
37};
38
39static void __iomem * __init earlycon_map(resource_size_t paddr, size_t size)
40{
41 void __iomem *base;
42#ifdef CONFIG_FIX_EARLYCON_MEM
43 set_fixmap_io(FIX_EARLYCON_MEM_BASE, paddr & PAGE_MASK);
44 base = (void __iomem *)__fix_to_virt(FIX_EARLYCON_MEM_BASE);
45 base += paddr & ~PAGE_MASK;
46#else
47 base = ioremap(paddr, size);
48#endif
49 if (!base)
50 pr_err("%s: Couldn't map %pa\n", __func__, &paddr);
51
52 return base;
53}
54
55static void __init earlycon_init(struct earlycon_device *device,
56 const char *name)
57{
58 struct console *earlycon = device->con;
59 struct uart_port *port = &device->port;
60 const char *s;
61 size_t len;
62
63 /* scan backwards from end of string for first non-numeral */
64 for (s = name + strlen(name);
65 s > name && s[-1] >= '0' && s[-1] <= '9';
66 s--)
67 ;
68 if (*s)
69 earlycon->index = simple_strtoul(s, NULL, 10);
70 len = s - name;
71 strlcpy(earlycon->name, name, min(len + 1, sizeof(earlycon->name)));
72 earlycon->data = &early_console_dev;
73
74 if (port->iotype == UPIO_MEM || port->iotype == UPIO_MEM16 ||
75 port->iotype == UPIO_MEM32 || port->iotype == UPIO_MEM32BE)
76 pr_info("%s%d at MMIO%s %pa (options '%s')\n",
77 earlycon->name, earlycon->index,
78 (port->iotype == UPIO_MEM) ? "" :
79 (port->iotype == UPIO_MEM16) ? "16" :
80 (port->iotype == UPIO_MEM32) ? "32" : "32be",
81 &port->mapbase, device->options);
82 else
83 pr_info("%s%d at I/O port 0x%lx (options '%s')\n",
84 earlycon->name, earlycon->index,
85 port->iobase, device->options);
86}
87
88static int __init parse_options(struct earlycon_device *device, char *options)
89{
90 struct uart_port *port = &device->port;
91 int length;
92 resource_size_t addr;
93
94 if (uart_parse_earlycon(options, &port->iotype, &addr, &options))
95 return -EINVAL;
96
97 switch (port->iotype) {
98 case UPIO_MEM:
99 port->mapbase = addr;
100 break;
101 case UPIO_MEM16:
102 port->regshift = 1;
103 port->mapbase = addr;
104 break;
105 case UPIO_MEM32:
106 case UPIO_MEM32BE:
107 port->regshift = 2;
108 port->mapbase = addr;
109 break;
110 case UPIO_PORT:
111 port->iobase = addr;
112 break;
113 default:
114 return -EINVAL;
115 }
116
117 if (options) {
118 device->baud = simple_strtoul(options, NULL, 0);
119 length = min(strcspn(options, " ") + 1,
120 (size_t)(sizeof(device->options)));
121 strlcpy(device->options, options, length);
122 }
123
124 return 0;
125}
126
127static int __init register_earlycon(char *buf, const struct earlycon_id *match)
128{
129 int err;
130 struct uart_port *port = &early_console_dev.port;
131
132 /* On parsing error, pass the options buf to the setup function */
133 if (buf && !parse_options(&early_console_dev, buf))
134 buf = NULL;
135
136 spin_lock_init(&port->lock);
137 port->uartclk = BASE_BAUD * 16;
138 if (port->mapbase)
139 port->membase = earlycon_map(port->mapbase, 64);
140
141 earlycon_init(&early_console_dev, match->name);
142 err = match->setup(&early_console_dev, buf);
143 if (err < 0)
144 return err;
145 if (!early_console_dev.con->write)
146 return -ENODEV;
147
148 register_console(early_console_dev.con);
149 return 0;
150}
151
152/**
153 * setup_earlycon - match and register earlycon console
154 * @buf: earlycon param string
155 *
156 * Registers the earlycon console matching the earlycon specified
157 * in the param string @buf. Acceptable param strings are of the form
158 * <name>,io|mmio|mmio32|mmio32be,<addr>,<options>
159 * <name>,0x<addr>,<options>
160 * <name>,<options>
161 * <name>
162 *
163 * Only for the third form does the earlycon setup() method receive the
164 * <options> string in the 'options' parameter; all other forms set
165 * the parameter to NULL.
166 *
167 * Returns 0 if an attempt to register the earlycon was made,
168 * otherwise negative error code
169 */
170int __init setup_earlycon(char *buf)
171{
172 const struct earlycon_id **p_match;
173
174 if (!buf || !buf[0])
175 return -EINVAL;
176
177 if (early_con.flags & CON_ENABLED)
178 return -EALREADY;
179
180 for (p_match = __earlycon_table; p_match < __earlycon_table_end;
181 p_match++) {
182 const struct earlycon_id *match = *p_match;
183 size_t len = strlen(match->name);
184
185 if (strncmp(buf, match->name, len))
186 continue;
187
188 if (buf[len]) {
189 if (buf[len] != ',')
190 continue;
191 buf += len + 1;
192 } else
193 buf = NULL;
194
195 return register_earlycon(buf, match);
196 }
197
198 return -ENOENT;
199}
200
201/*
202 * This defers the initialization of the early console until after ACPI has
203 * been initialized.
204 */
205bool earlycon_acpi_spcr_enable __initdata;
206
207/* early_param wrapper for setup_earlycon() */
208static int __init param_setup_earlycon(char *buf)
209{
210 int err;
211
212 /* Just 'earlycon' is a valid param for devicetree and ACPI SPCR. */
213 if (!buf || !buf[0]) {
214 if (IS_ENABLED(CONFIG_ACPI_SPCR_TABLE)) {
215 earlycon_acpi_spcr_enable = true;
216 return 0;
217 } else if (!buf) {
218 return early_init_dt_scan_chosen_stdout();
219 }
220 }
221
222 err = setup_earlycon(buf);
223 if (err == -ENOENT || err == -EALREADY)
224 return 0;
225 return err;
226}
227early_param("earlycon", param_setup_earlycon);
228
229#ifdef CONFIG_OF_EARLY_FLATTREE
230
231int __init of_setup_earlycon(const struct earlycon_id *match,
232 unsigned long node,
233 const char *options)
234{
235 int err;
236 struct uart_port *port = &early_console_dev.port;
237 const __be32 *val;
238 bool big_endian;
239 u64 addr;
240
241 spin_lock_init(&port->lock);
242 port->iotype = UPIO_MEM;
243 addr = of_flat_dt_translate_address(node);
244 if (addr == OF_BAD_ADDR) {
245 pr_warn("[%s] bad address\n", match->name);
246 return -ENXIO;
247 }
248 port->mapbase = addr;
249
250 val = of_get_flat_dt_prop(node, "reg-offset", NULL);
251 if (val)
252 port->mapbase += be32_to_cpu(*val);
253 port->membase = earlycon_map(port->mapbase, SZ_4K);
254
255 val = of_get_flat_dt_prop(node, "reg-shift", NULL);
256 if (val)
257 port->regshift = be32_to_cpu(*val);
258 big_endian = of_get_flat_dt_prop(node, "big-endian", NULL) != NULL ||
259 (IS_ENABLED(CONFIG_CPU_BIG_ENDIAN) &&
260 of_get_flat_dt_prop(node, "native-endian", NULL) != NULL);
261 val = of_get_flat_dt_prop(node, "reg-io-width", NULL);
262 if (val) {
263 switch (be32_to_cpu(*val)) {
264 case 1:
265 port->iotype = UPIO_MEM;
266 break;
267 case 2:
268 port->iotype = UPIO_MEM16;
269 break;
270 case 4:
271 port->iotype = (big_endian) ? UPIO_MEM32BE : UPIO_MEM32;
272 break;
273 default:
274 pr_warn("[%s] unsupported reg-io-width\n", match->name);
275 return -EINVAL;
276 }
277 }
278
279 val = of_get_flat_dt_prop(node, "current-speed", NULL);
280 if (val)
281 early_console_dev.baud = be32_to_cpu(*val);
282
283 val = of_get_flat_dt_prop(node, "clock-frequency", NULL);
284 if (val)
285 port->uartclk = be32_to_cpu(*val);
286
287 if (options) {
288 early_console_dev.baud = simple_strtoul(options, NULL, 0);
289 strlcpy(early_console_dev.options, options,
290 sizeof(early_console_dev.options));
291 }
292 earlycon_init(&early_console_dev, match->name);
293 err = match->setup(&early_console_dev, options);
294 if (err < 0)
295 return err;
296 if (!early_console_dev.con->write)
297 return -ENODEV;
298
299
300 register_console(early_console_dev.con);
301 return 0;
302}
303
304#endif /* CONFIG_OF_EARLY_FLATTREE */
1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Copyright (C) 2014 Linaro Ltd.
4 * Author: Rob Herring <robh@kernel.org>
5 *
6 * Based on 8250 earlycon:
7 * (c) Copyright 2004 Hewlett-Packard Development Company, L.P.
8 * Bjorn Helgaas <bjorn.helgaas@hp.com>
9 */
10
11#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
12
13#include <linux/console.h>
14#include <linux/kernel.h>
15#include <linux/init.h>
16#include <linux/io.h>
17#include <linux/serial_core.h>
18#include <linux/sizes.h>
19#include <linux/of.h>
20#include <linux/of_fdt.h>
21#include <linux/acpi.h>
22
23#ifdef CONFIG_FIX_EARLYCON_MEM
24#include <asm/fixmap.h>
25#endif
26
27#include <asm/serial.h>
28
29static struct console early_con = {
30 .name = "uart", /* fixed up at earlycon registration */
31 .flags = CON_PRINTBUFFER | CON_BOOT,
32 .index = 0,
33};
34
35static struct earlycon_device early_console_dev = {
36 .con = &early_con,
37};
38
39static void __iomem * __init earlycon_map(resource_size_t paddr, size_t size)
40{
41 void __iomem *base;
42#ifdef CONFIG_FIX_EARLYCON_MEM
43 set_fixmap_io(FIX_EARLYCON_MEM_BASE, paddr & PAGE_MASK);
44 base = (void __iomem *)__fix_to_virt(FIX_EARLYCON_MEM_BASE);
45 base += paddr & ~PAGE_MASK;
46#else
47 base = ioremap(paddr, size);
48#endif
49 if (!base)
50 pr_err("%s: Couldn't map %pa\n", __func__, &paddr);
51
52 return base;
53}
54
55static void __init earlycon_init(struct earlycon_device *device,
56 const char *name)
57{
58 struct console *earlycon = device->con;
59 const char *s;
60 size_t len;
61
62 /* scan backwards from end of string for first non-numeral */
63 for (s = name + strlen(name);
64 s > name && s[-1] >= '0' && s[-1] <= '9';
65 s--)
66 ;
67 if (*s)
68 earlycon->index = simple_strtoul(s, NULL, 10);
69 len = s - name;
70 strlcpy(earlycon->name, name, min(len + 1, sizeof(earlycon->name)));
71 earlycon->data = &early_console_dev;
72}
73
74static void __init earlycon_print_info(struct earlycon_device *device)
75{
76 struct console *earlycon = device->con;
77 struct uart_port *port = &device->port;
78
79 if (port->iotype == UPIO_MEM || port->iotype == UPIO_MEM16 ||
80 port->iotype == UPIO_MEM32 || port->iotype == UPIO_MEM32BE)
81 pr_info("%s%d at MMIO%s %pa (options '%s')\n",
82 earlycon->name, earlycon->index,
83 (port->iotype == UPIO_MEM) ? "" :
84 (port->iotype == UPIO_MEM16) ? "16" :
85 (port->iotype == UPIO_MEM32) ? "32" : "32be",
86 &port->mapbase, device->options);
87 else
88 pr_info("%s%d at I/O port 0x%lx (options '%s')\n",
89 earlycon->name, earlycon->index,
90 port->iobase, device->options);
91}
92
93static int __init parse_options(struct earlycon_device *device, char *options)
94{
95 struct uart_port *port = &device->port;
96 int length;
97 resource_size_t addr;
98
99 if (uart_parse_earlycon(options, &port->iotype, &addr, &options))
100 return -EINVAL;
101
102 switch (port->iotype) {
103 case UPIO_MEM:
104 port->mapbase = addr;
105 break;
106 case UPIO_MEM16:
107 port->regshift = 1;
108 port->mapbase = addr;
109 break;
110 case UPIO_MEM32:
111 case UPIO_MEM32BE:
112 port->regshift = 2;
113 port->mapbase = addr;
114 break;
115 case UPIO_PORT:
116 port->iobase = addr;
117 break;
118 default:
119 return -EINVAL;
120 }
121
122 if (options) {
123 device->baud = simple_strtoul(options, NULL, 0);
124 length = min(strcspn(options, " ") + 1,
125 (size_t)(sizeof(device->options)));
126 strlcpy(device->options, options, length);
127 }
128
129 return 0;
130}
131
132static int __init register_earlycon(char *buf, const struct earlycon_id *match)
133{
134 int err;
135 struct uart_port *port = &early_console_dev.port;
136
137 /* On parsing error, pass the options buf to the setup function */
138 if (buf && !parse_options(&early_console_dev, buf))
139 buf = NULL;
140
141 spin_lock_init(&port->lock);
142 port->uartclk = BASE_BAUD * 16;
143 if (port->mapbase)
144 port->membase = earlycon_map(port->mapbase, 64);
145
146 earlycon_init(&early_console_dev, match->name);
147 err = match->setup(&early_console_dev, buf);
148 earlycon_print_info(&early_console_dev);
149 if (err < 0)
150 return err;
151 if (!early_console_dev.con->write)
152 return -ENODEV;
153
154 register_console(early_console_dev.con);
155 return 0;
156}
157
158/**
159 * setup_earlycon - match and register earlycon console
160 * @buf: earlycon param string
161 *
162 * Registers the earlycon console matching the earlycon specified
163 * in the param string @buf. Acceptable param strings are of the form
164 * <name>,io|mmio|mmio32|mmio32be,<addr>,<options>
165 * <name>,0x<addr>,<options>
166 * <name>,<options>
167 * <name>
168 *
169 * Only for the third form does the earlycon setup() method receive the
170 * <options> string in the 'options' parameter; all other forms set
171 * the parameter to NULL.
172 *
173 * Returns 0 if an attempt to register the earlycon was made,
174 * otherwise negative error code
175 */
176int __init setup_earlycon(char *buf)
177{
178 const struct earlycon_id *match;
179 bool empty_compatible = true;
180
181 if (!buf || !buf[0])
182 return -EINVAL;
183
184 if (early_con.flags & CON_ENABLED)
185 return -EALREADY;
186
187again:
188 for (match = __earlycon_table; match < __earlycon_table_end; match++) {
189 size_t len = strlen(match->name);
190
191 if (strncmp(buf, match->name, len))
192 continue;
193
194 /* prefer entries with empty compatible */
195 if (empty_compatible && *match->compatible)
196 continue;
197
198 if (buf[len]) {
199 if (buf[len] != ',')
200 continue;
201 buf += len + 1;
202 } else
203 buf = NULL;
204
205 return register_earlycon(buf, match);
206 }
207
208 if (empty_compatible) {
209 empty_compatible = false;
210 goto again;
211 }
212
213 return -ENOENT;
214}
215
216/*
217 * This defers the initialization of the early console until after ACPI has
218 * been initialized.
219 */
220bool earlycon_acpi_spcr_enable __initdata;
221
222/* early_param wrapper for setup_earlycon() */
223static int __init param_setup_earlycon(char *buf)
224{
225 int err;
226
227 /* Just 'earlycon' is a valid param for devicetree and ACPI SPCR. */
228 if (!buf || !buf[0]) {
229 if (IS_ENABLED(CONFIG_ACPI_SPCR_TABLE)) {
230 earlycon_acpi_spcr_enable = true;
231 return 0;
232 } else if (!buf) {
233 return early_init_dt_scan_chosen_stdout();
234 }
235 }
236
237 err = setup_earlycon(buf);
238 if (err == -ENOENT || err == -EALREADY)
239 return 0;
240 return err;
241}
242early_param("earlycon", param_setup_earlycon);
243
244#ifdef CONFIG_OF_EARLY_FLATTREE
245
246int __init of_setup_earlycon(const struct earlycon_id *match,
247 unsigned long node,
248 const char *options)
249{
250 int err;
251 struct uart_port *port = &early_console_dev.port;
252 const __be32 *val;
253 bool big_endian;
254 u64 addr;
255
256 spin_lock_init(&port->lock);
257 port->iotype = UPIO_MEM;
258 addr = of_flat_dt_translate_address(node);
259 if (addr == OF_BAD_ADDR) {
260 pr_warn("[%s] bad address\n", match->name);
261 return -ENXIO;
262 }
263 port->mapbase = addr;
264
265 val = of_get_flat_dt_prop(node, "reg-offset", NULL);
266 if (val)
267 port->mapbase += be32_to_cpu(*val);
268 port->membase = earlycon_map(port->mapbase, SZ_4K);
269
270 val = of_get_flat_dt_prop(node, "reg-shift", NULL);
271 if (val)
272 port->regshift = be32_to_cpu(*val);
273 big_endian = of_get_flat_dt_prop(node, "big-endian", NULL) != NULL ||
274 (IS_ENABLED(CONFIG_CPU_BIG_ENDIAN) &&
275 of_get_flat_dt_prop(node, "native-endian", NULL) != NULL);
276 val = of_get_flat_dt_prop(node, "reg-io-width", NULL);
277 if (val) {
278 switch (be32_to_cpu(*val)) {
279 case 1:
280 port->iotype = UPIO_MEM;
281 break;
282 case 2:
283 port->iotype = UPIO_MEM16;
284 break;
285 case 4:
286 port->iotype = (big_endian) ? UPIO_MEM32BE : UPIO_MEM32;
287 break;
288 default:
289 pr_warn("[%s] unsupported reg-io-width\n", match->name);
290 return -EINVAL;
291 }
292 }
293
294 val = of_get_flat_dt_prop(node, "current-speed", NULL);
295 if (val)
296 early_console_dev.baud = be32_to_cpu(*val);
297
298 val = of_get_flat_dt_prop(node, "clock-frequency", NULL);
299 if (val)
300 port->uartclk = be32_to_cpu(*val);
301
302 if (options) {
303 early_console_dev.baud = simple_strtoul(options, NULL, 0);
304 strlcpy(early_console_dev.options, options,
305 sizeof(early_console_dev.options));
306 }
307 earlycon_init(&early_console_dev, match->name);
308 err = match->setup(&early_console_dev, options);
309 earlycon_print_info(&early_console_dev);
310 if (err < 0)
311 return err;
312 if (!early_console_dev.con->write)
313 return -ENODEV;
314
315
316 register_console(early_console_dev.con);
317 return 0;
318}
319
320#endif /* CONFIG_OF_EARLY_FLATTREE */